I'd ask Danfoss customer service about the compatibility of this thermostat with this central system. They surely know. They can provide you with the installation instructions also.
Moreover, if the shop where you buy your stuff can't tell if it's compatible, if the installation instruction is coming with the product and if installing it is a DIY job for you, I'd look for shop with a better pre-sales service.
Kees
is it possible to fit
a battery operated 2 WIRE danfoss rt51 digital room thermostat TO A danfoss randall 3 WIRE 103e5 central heating system ?
how do i do it and, is it easy or do i need a plumber to fit it for me
many thanks

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